Sorry, I forgot to correct that.
What I know now is that my FBX was shipped from USA to Portugal (where I live) around one and a half years ago (bought in Reverb, btw).And from the portuguese owners, I am the 3rd one.
The 2nd portuguese owner said that he never registered the guitar, so I'm trying to talk to the 1st portuguese owner. If he said that he did not registered it as well, I will try to talk with the last USA owner, and so on.
If things work out fine, I might be able to access the account that was created in first place. Otherwise, I may contact Gibson to try to solve this